Lock for sliding doors

ABSTRACT

This lock device consist primarily of a body portion having a lever arm which engages a latch plate, the lever arm serving to prevent disengagement of the latch plate when the device is in lock position.

United States Patent East et al. May 20, 1975 [54] LOCK FOR SLIDINGDOORS 1,675,176 6/1928 Jarecki 292/332 2,232,965 2/1941 Perl 292/226[76] Inventors? East; East both of 2,659,621 11 1953 Jacobson 292 240920 82nd "102, Scottsdale, 2,789,852 4/1957 Eads 292/110 Ariz. 85257[22] Filed: Oct. 5, 1973 pp NO 403 930 Primary ExaminerAlbert G. Craig,Jr.

[52] US. Cl. 70/100; 70/D1G. 52; 292/98;

292/197; 292/210 57 ABSTRACT [51] Int. Cl Eb /08 1 [58] Field of Search/100, 136, 137, 142,

70/DIG. 52; 292/96, 98, 100, 124 12 Th1s lock device conslst prlrnarllyof a body portion 129 197 200 210 224 22 229 DIG 49 having a lever armwhich engages a latch plate, the lever arm serving to preventdisengagement of the [56] References Cited latch plate when the deviceis in look position.

UNITED STATES PATENTS 834,743 10/1906 Mason 292/98 6 Claims, 4 DrawingFigures LOCK FOR SLIDING DOORS;

This invention relates to door locks, and more particularly to a lockfor sliding dOOISgfl} I It is therefore the principal object ofthisinvention to provide a lock for, sliding doorswhich will be of suchstructure, so as to prevent disengagerrient of the lock with a rhythmicmotion ofa bar onto the door a practice common in the unauthorizedopening of sliding doors leading to a patioor balcony. Anotherobject ofthis invention is to provide a lock which will have spring loaded levera r m means which will prevent the disengagement of a latch plate whenthe door is locked.

A further object of this invention is to provide a lock of the typedescribed, of which the lever arm will serve as a prop for the latchplate when the door is locked, the lock body including a stop pin so asto prevent overthrow of the lever arm.

A further object of this invention is to provide a two componentlatching device, the components being kept in proper relation to eachother by an open recess in one component, namely the latch plate,receiving an end of the other component, namely the lever arm.

A further object of this invention is to provide a latching deviceincluding two independently pivotally mounted components, one being alatch plate with a conventional lip for engagement with a keeper orstrike plate and the other being a lever arm serving as a prop for thelatch plate when in the latching position.

A further object of this invention is to provide a latching deviceincluding two main components independently mounted with no mechanicallinkage tying the two components together, one component being a leverarm, and further including a stop pin to limit travel of the lever armto its latching position and a conventional overcenter loading spring toexert pressure on the lever arm against the stop pin.

A further object is to provide a latching device including two pivotallysupported components whose pivot points and point of mutual contact forma 90 angle that is not altered by any means other than key or thumb turnoperation, the bearing point not being altered by wearv A further objectis to provide a latching device including a latch plate and a lever arm,the latch plate being of solid construction, not being sliced, drilledor mutilated in any way by removal of metal for a mechanical tie withthe lever arm thus maintaining sufficient strength to eliminate thenecessity of any type of reinforcing device to save the structure fromdamage.

Other objects of the invention are to provide a lock which has a minimumnumber of parts, is simple in design, inexpensive to manufacture, ruggedin construction, of such size and strength as to prevent damage by shockin use or misuse, easy to use and efficient inoperation.

These and other objects will be readily evident upon a study of thefollowing specification and the accompanying drawing, wherein:

FIG. 1 is a cross-sectional view taken along the line I1 of FIG. 3;

FIG. 2 is similar to FIG. 1, but shows the device in open position;

FIG. 3 is a rear end view of the device;

FIG. 4 is a fragmentary end view of a door showing the device installedthereon.

: According to this invention, a lock. 10 is shown to t have a body 11with spacers 12 having openings 13 the Latch plate 14 includes a lip 14adefined by a recess 16 and the opposite end of latch plate 14 includes alip 17 defined by recess 18. The lip 14a of latch plate 14, serves toengage the keeper or strike plate 15a mounted to the door jamb 15b. Apivotable lever arm 19 is secured fixedly to member 20 of the lockcylinder, and member 20 includes a retangular slot 20a. A pin 21 throughmember 20, carries a rod 22 which is encompassed by means of a coiledspring 23, the rod 22 also extending through pin 24.

Looking now at FIGS. 1 and 2 of the drawing, it will be seen that body11 of lock 10, is provided with a stop pin 25 against which lever arm 19abuts when .lock 10 is closed. 1

The lock cylinder (not shown) has a stern engaging lever arm 19 by meansof the slot 20a, the stem also connecting with thumb turn type of knobor handle 26.

It will be seen that the spring 23 serves as means for adding pressureto the end of lever arm 19 in both, the open and closed positions.

It shall be noted that the particularly lock design herein described,makes possible for the shortest opening in the door stile in which thelock 10 is inserted.

Referring again to FIG. 1 of the drawing, it will be seen that one endof lever arm 19 engages the periphery of the recess 18, thus preventingthe rotation of latch plate 14 and the disengagement of the lip 14a fromthe keeper or strike plate 15a secured to the door jamb 15b.

It shall also be noted that lock 10 is adaptable to various types ofexisting handles, by making small variations in the design of thecomponents herein described, however, the principal of operation remainsthe same.

What I now claim is:

l. A latch mechanism for a slidable door comprising: a hollow body, alatch plate having lip means adapted to releasably grasp a keeper, firstpivot means pivotally supporting said latch plate within said body, alever arm, second pivot means pivotally supporting said lever arm withinsaid body, the axes of the two pivot means being spaced andsubstantially parallel, said latch plate being defined in part by aperipheral recess generally facing toward said second pivot means andreceiving the distal end of said lever arm, said peripheral recess beingshaped in such a manner as to form a cam and follower relationship withsaid distal end of the lever arm so that pivotal movement of said leverarm will cause pivotal movement of said latch plate between a keepergrasping, or latching, position and an unlatching position, saidperipheral'recess also being shaped such that when the latch plate is inits latching position the lever arm will be in contact with a planarportion thereof, the planar portion lying in a plane containing the axisof said first pivot means and being perpendicular to a second planecontaining the axis of said second pivot means and the point of contactof the lever arm with said planar portion, so that all external pressureapplied directly to said latch plate in an attempt to pivot it towardits unlatching position will be applied through said lever arm directlyto said second pivot means, manually accessible means for pivoting saidlever arm, and stop means fixedly carried within said body and limitingpivotal movement of said leverarm in one direction to that positionwherein the distal end thereof abuts said planar portion of saidperipheral recess of said latch plate.

2. A latch mechanism as defined in claim 1 wherein said first pivotmeans includes a pin secured within said hollow body and snugly passingthrough the only opening through said latch plate.

3. A latch mechanism as defined in claim 1 wherein said second pivotmeans includes a cylinder fixedly secured to said lever arm withopposite ends thereof extending through opposed walls of said hollowbody and said manually accessible means includes a key operated cylinderlock interconnected with one end of said cylinder.

4. A latchmechanisin as defined in claim 3 wherein said manuallyaccessible means further includes a thumb turn type of knobinterconnected with the other end of said cylinder.

5. A latch mechanism asdefined in claim 1 wherein said stop means is inthe nature of a pin extend across said hollow body and secured toopposed walls thereof.

6. A latch mechanism as defined in claim 1 wherein said hollow body isadapted to be supported within a mortise in an edge of a stile of aslidable door.

1. A latch mechanism for a slidable door comprising: a hollow body, alatch plate having lip means adapted to releasably grasp a keeper, firstpivot means pivotally supporting said latch plate within said body, alever arm, second pivot means pivotally supporting said lever arm withinsaid body, the axes of the two pivot means being spaced andsubstantially parallel, said latch plate being defined in part by aperipheral recess generally facing toward said second pivot means andreceiving the distal end of said lever arm, said peripheral recess beingshaped in such a manner as to form a cam and follower relationship withsaid distal end of the lever arm so that pivotal movement of said leverarm will cause pivotal movement of said latch plate between a keepergrasping, or latching, position and an unlatching position, saidperipheral recess also being shaped such that when the latch plate is inits latching position the lever arm will be in contact with a planarportion thereof, the planar portion lying in a plane containing the axisof said first pivot means and being perpendicular to a second planecontaining the axis of said second pivot means and the point of contactof the lever arm with said planar portion, so that all external pressureapplied directly to said latch plate in an attempt to pivot it towardits unlatching position will be applied through said lever arm directlyto said second pivot means, manually accessible means for pivoting saidlever arm, and stop means fixedly carried within said body and limitingpivotal movement of said lever arm in one direction to that positionwherein the distal end thereof abuts said planar portion of saidperipheral recess of said latch plate.
 2. A latch mechanism as definedin claim 1 wherein said first pivot means includes a pin secured withinsaid hollow body and snugly passing through the only opening throughsaid latch plate.
 3. A latch mechanism as defined in claim 1 whereinsaid second pivot means includes a cylinder fixedly secured to saidlever arm with opposite ends thereof extending through opposed walls ofsaid hollow body and said manually accessible means includes a keyoperated cylinder lock interconnected with one end of said cylinder. 4.A latch mechanism as defined in claim 3 wherein said manually accessiblemeans further includes a thumb turn type of knob interconnected with theother end of said cylinder.
 5. A latch mechanism as defined in claim 1wherein said stop means is in the nature of a pin extend across saidhollow body and secured to opposed walls thereof.
 6. A latch mechanismas defined in claim 1 wherein said hollow body is adapted to besupported within a mortise in an edge of a stile of a slidable door.